JP2940323B2 - Control device for rubber kneader and control method therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber kneader control device for controlling the kneading state (kneading degree) of a kneaded material in a rubber kneader and a control method therefor.

[0002]

2. Description of the Related Art Conventionally, when rubber materials are kneaded with a closed kneader such as a Banbury mixer or a vertical kneader, a raw material rubber, carbon black, oil and various compounding agents are charged, and then a pressing member such as a floating weight is lowered. . The rubber kneading machine starts kneading at a preset rotation speed of the rotor (rotating member), and determines the kneading state of the kneaded material by detecting the maximum value of the load power value (torque value) of the drive motor. A method for controlling the kneading time is known.

As a method of detecting the maximum value of the load power value, first, a predetermined number of instantaneous load power values from the drive motor are sampled at a predetermined frequency, and a moving average value is calculated. The moving average value is obtained as a value obtained by adding all the sampling values P _1, P _2, ... _, P _n at predetermined intervals within a predetermined time before the current time and dividing by the number of samples n. That is, the moving average value Dn is calculated at predetermined intervals by the following equation.

[Number 1] _{Dn = (P 1 + P 2} + ... + P n) / n Next, the current value of the moving average value is compared with the maximum value up to that, beyond the maximum current value of the moving average value The current value is updated as the maximum value,
When the current value of the moving average value does not exceed the maximum value, the falling value is determined without updating the maximum value. The maximum value in the case where the moving average value continuously falls a predetermined number of times without exceeding the maximum value is set as a true maximum value and is used as a guide for judging the kneading state of the kneaded material.

FIG. 7 is a chart showing a transition of a load power value represented by a moving average value in general rubber kneading of a rubber kneading machine. In the rubber kneader, first, a raw material rubber, carbon black, an oil, a compounding agent, and the like are first charged as raw materials of the kneaded material, and the first kneading is performed. Following the first kneading, there is a second input of a compounding agent and the like. When the second kneading is completed, the kneaded material is discharged from the rubber kneader as the kneading is completed.

[0005]

However, in the chart (waveform) showing the load power value shown in FIG. 7, the rising and falling of the large peak appearing in the first kneading (between the first input and the second input). In some cases, the shape did not appear in the same manner even when the kneaded materials having the same composition were kneaded. That is, in some charts, the load power value does not reach the maximum value when it should be the maximum value. This difference will be described with reference to the charts of FIGS. 8 and 9 showing the relationship between the kneading time and the load power value in the first kneading. Generally, in the chart of the load power value of the drive motor of the kneading machine, the value rapidly increases immediately after the start of kneading, and a first peak occurs. Next, when the load power value gradually decreases and the kneading progresses to some extent, the value increases again and then decreases to form a second peak. The time from the first mountain to the second mountain is BIT (Black Incorporatio
n Time), and the second peak is known as an indicator of the dispersion of carbon black.

[0008] In the chart shown in FIG. 8, if the above-mentioned second mountain is looked at in more detail, there are also two mountains there and the maximum value of the moving average value. The kneading completion signal is output after a predetermined time (15 seconds). In this case, a good kneaded state of the kneaded material can be obtained without any problem in the first kneading. On the other hand, in the chart as shown in FIG. 9, the first peak is higher than the second peak and has the maximum value of the moving average value. Therefore, if a kneading completion signal is output after a predetermined time (15 sec) from this maximum value, kneading is in progress, and a good kneading state of the kneaded material cannot be obtained in the first kneading. As described above, even if the chart has the same two peaks, the output time of the kneading completion determination signal in the first kneading is different, and the required time changes and the kneaded dough after the kneading is completed. Physical property values were a factor of variation.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to stabilize the physical properties of a kneaded material kneaded by a rubber kneader.

[0008]

The first feature of the present invention for solving the above-mentioned problem is that, as shown in FIG. 10, the concept is as follows. Using a closed kneader having a pair of rotating members that rotate to a rotating member and a pressing member that is driven so as to be close to the rotating members, a kneaded material comprising a raw material rubber and an additive such as carbon black that have been charged In a rubber kneader control device in which the pressing member presses and kneads the kneaded material between the rotating members and kneads the mixture by the rotation of the rotating member, the rotating member of the kneading machine is rotationally driven during kneading. A physical quantity detecting means G01 for detecting a physical quantity related to the load of the driving source at predetermined time intervals; and the physical quantity detecting means G0.
A maximum value detection means G02 for obtaining a maximum value of the physical quantity detected by 1; and a judgment value setting means G0 for setting a value reduced by a predetermined amount from the maximum value of the physical quantity as a judgment value.
3 and a kneading time for determining a kneading end time based on a transition from a point in time when the current value of the physical quantity detected by the physical quantity detecting means G01 exceeds the determination value set by the determination value setting means G03. Decision means G04.

A second feature is that a pair of rotating members arranged adjacent to each other and rotating in opposite directions so as to be wound inward, and a pressing member driven close to the rotating members are provided. Using a closed kneader having, the kneaded material comprising the added raw material rubber and additives such as carbon black is kneaded by the rotation of the rotating member and the pressing member presses the kneaded material between the rotating members. In the control method for a rubber kneader, the physical quantity related to the load of a drive source that rotationally drives the rotating member of the kneader during kneading is detected at predetermined time intervals, and the maximum value of the detected physical quantity is determined. A value that is reduced by a predetermined amount from the maximum value of the physical quantity is set as a determination value, and the end of kneading is determined based on a transition from the time when the detected current value of the physical quantity exceeds the set determination value. It is to determine the time.

[0010]

According to the above means, the physical quantity related to the load of the driving source for rotating the rotary member of the kneader during kneading is detected every predetermined time. As the physical quantity, for example, a value that directly indicates a load such as a load power value or a current value of a drive motor, or a value that indirectly indicates a load such as a temperature of a kneaded material or a volume generated from a kneader is used. As the physical quantity, a physical quantity whose predetermined range is known in advance depending on the kind and temperature of the kneaded material is adopted. Further, the maximum value of the physical quantity is sequentially updated by comparison with the previous value, and at the same time, a value reduced by a predetermined amount from the maximum value of the physical quantity is set as the determination value. This determination value is set to be larger than the range in consideration of the fluctuation range when the physical quantity detected every predetermined time shows an unstable value during kneading. Therefore, any fall or rise of the physical quantity detected every predetermined time period from the maximum value of the physical quantity to the determination value is ignored. Since the transition of the physical quantity is stable from the time when the current value of the physical quantity detected every predetermined time exceeds the determination value, the kneading end time is accurately determined based on the transition.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific embodiments. FIG. 2 is a configuration diagram schematically showing a rubber kneader to which the control device for a rubber kneader according to the present invention is applied. The rubber kneader 10 includes a kneading chamber 1, an air cylinder device 2 fixed above the kneading chamber 1, a pair of rotors 3 arranged in the kneading chamber 1, and a piston rod 2 a of the air cylinder device 2.
Floating weight 4 held at the tip of the rotor and driven in a direction approaching and away from the pair of rotors 3
And a hopper 5 for charging the kneaded material into the kneading chamber 1;
And a drop door 6 for taking out the kneaded mixture. The pair of rotors 3 are connected to a drive motor 12 whose rotation is controlled by a motor drive circuit 11.

The pair of rotors 3 are driven to rotate in opposite directions, and the kneaded material is wound between the pair of rotors 3 from above to below. Therefore, during kneading, a large amount of the kneaded material gathers above the portion between the pair of rotors 3, and the kneading is performed while the floating weight 4 presses the kneaded material in that portion toward the rotor 3.

FIG. 1 is a block diagram showing a control device for a rubber kneader according to the present invention. In this embodiment, the drive motor 1 is used as a physical quantity related to the load of the drive motor 12.
An instantaneous load power value of 2 was used. Control device 2 for rubber kneader
0 mainly includes a CPU 23, a ROM 24 storing a control program, and a RAM 25 storing various data. The instantaneous load power value from the drive motor 12 is A
CPU via a / D converter 21 and an interface 22
23. Further, an output signal from the CPU 23 is output to the motor drive circuit 11 via the interface 22, and the rotation of the drive motor 12 is controlled by the output signal.

In the RAM 25, a load power value storage area 251, which stores the instantaneous load power value from the drive motor 12 for a predetermined number of samplings at a predetermined sampling time,
A moving average value storage area 252 for storing the moving average value (Dn) of the instantaneous load power value, a maximum value storage area 253 for storing the maximum moving average value (Dn _MAX ), and a maximum value of the moving average value (Dn)
n _MAX ), a predetermined value storage area 254 for storing a predetermined value (K) for setting a mask line, which is the lower limit of the range in which the falling count is not performed, corresponding to the falling count value at the end of the first kneading And a set value storage area 255 for storing set values to be set. In the load power value storage area 251, after the predetermined number of samplings is stored, the latest value is updated one by one instead of the oldest value. As the contents of the load power value storage area 251 are updated, the contents of the moving average value storage area 252 are also updated.

Next, the CP used in the apparatus of this embodiment is
A description will be given based on the flowcharts of FIGS. 3 and 4 showing the processing procedure of U23. Note that this program is the same as that shown in FIG.
At the end of the kneading in the first kneading. First, in step 100 of FIG. 3, setting of initial conditions is executed. Next, the process proceeds to step 102, where a kneading start command is output. Next, the routine proceeds to step 104, where it is determined whether the peak detection start time has elapsed. That is, the time from the start of kneading when the kneading is normal to the time when the maximum value Dn _MAX of the moving average value of the instantaneous load power value appears is almost known, and the peak detection start time set slightly before that time elapses. You do not need to execute this program until you do. When the peak detection start time has elapsed, the routine proceeds to step 106, where it is determined whether or not the peak line has been exceeded. That is, the magnitude of the maximum value Dn _MAX when kneading is normal is almost known, and it is not necessary to execute the contents of this program until a peak line slightly lower than the maximum value is exceeded.

When the magnitude of the maximum value Dn _MAX exceeds the peak line, sampling is started and the process proceeds to step 108, at which the instantaneous load power value P ₁ (KW) from the drive motor 12 is read. This value is stored in the load power value storage area 2 of the RAM 25.
51 is stored. Next, the routine proceeds to step 110, where a moving average value Dn (KW) is calculated. At this time, if the number of samples is less than a preset number of samples (for example, i = 1, 2,..., 10 when the number is 10), a moving average value Dn (KW) is calculated based on only those values. It is stored in the moving average value storage area 252 of the RAM 25. Next, step 112
Then, it is determined whether or not i = 1. Immediately after the start of sampling, i = 1, so that the process proceeds to step 114, and the moving average value Dn is stored in the maximum value storage area 253 of the RAM 25 as the maximum value Dn _MAX of the moving average value.

Next, the routine proceeds to step 116, where a predetermined sampling time (for example, 0.2 seconds) is set as the predetermined time.
After waiting for ec) to elapse, the process returns to the above-described step 108, and similarly performs the processing of steps 108 and 110. Then, in step 112, i = is determined as 2. The term for NO and proceeds to step 118, the inequality of Dn> Dn _MAX is determined. If the inequality sign is satisfied in step 118, the moving average value Dn of the instantaneous load power value is in a rising state, and the process proceeds to step 120, where the latest moving average value Dn is set as the maximum value Dn _MAX of the moving average value in the maximum value storage area of the RAM 25. 2
53. Next, at step 122, the falling flag is turned off, and at step 124, the falling count is cleared. After that, the process returns to step 116, and the same processing is executed.

If the inequality sign does not hold in step 118, the moving average value Dn of the instantaneous load power value is in a falling state, and the routine goes to step 126 in FIG. In step 126, it is determined whether or not the falling flag is on. At first, since the falling flag is not on, the falling flag is turned on in step 128, 1 is added to the falling count in step 130, and the process returns to the above-mentioned step 116 to execute the same processing.

If the falling flag is ON in step 126, the process proceeds to step 132, where Dn <Dn _MAX
Is determined. If the inequality sign in step 132 is not satisfied, the process returns to step 116, and the same processing is performed thereafter. In step 132, when the inequality sign is satisfied, the moving average value Dn of the instantaneous load power value is in a falling state, and the process shifts to step 134 to determine whether or not the inequality Dn _MAX -Dn> K is satisfied.

The above K (KW) is a predetermined load power value previously stored as a predetermined value in a predetermined value storage area 254 of the RAM 25, and is equal to a predetermined load power value from the maximum value Dn _MAX of the moving average value. Is used to mask the rising and falling states of. The predetermined load power value K corresponding to this mask is set in advance to be larger than the load power that is expected to fluctuate at the rise and fall. Therefore, no fluctuation of the rise and fall within the predetermined load power value K is added to the fall count.

If the inequality sign does not hold in step 134, the process returns to step 116, and the same processing is performed thereafter. When the inequality in step 134 is satisfied and the moving average value Dn falls below the maximum value Dn _{MAX by the} amount exceeding the above K (KW), the process proceeds to step 136, and 1 is added to the falling count. Next, the routine proceeds to step 138, where it is determined whether or not the falling count value is equal to the set value. This set value is stored in the set value storage area 2 of the RAM 25.
55, and corresponds to the falling count value at the end of the first kneading. If the falling count value has not reached the set value, the process returns to step 116, and the same processing is performed thereafter. Then, step 138
When the falling count value reaches the set value, the program for controlling the first kneading is terminated.

Here, a description will be given of a case where the above-mentioned program shown in FIGS. 3 and 4 is applied to the chart showing the relationship between the kneading time and the load power value in the first kneading shown in FIGS. 5 and 6. In the chart of the moving average value of the instantaneous load power value shown in FIG. 5, the maximum value Dn _MAX of the moving average value appears on the second peak in the kneading, and the maximum value Dn _MAX
After that, the moving average value Dn detected and read every predetermined time (0.2 sec) continuously falls. Therefore, when the moving average value Dn becomes a load power value that is lower than the maximum value Dn _MAX by the load power value K, the falling count is sequentially added, and when the set value is 50, 10 seconds (= 0.2 × 5)
0) After that, the first kneading end signal will be output.

On the other hand, in the chart of the moving average value of the instantaneous load power value shown in FIG. 6, the maximum value Dn _MAX of the moving average value appears earlier in the first peak, and its maximum value Dn _MAX
, The moving average value Dn detected and read at every predetermined time (0.2 sec) is a curve that extends long in the latter half. In this case, the load power value K determined in step 134 in the program of FIG. That is, even if there is a falling rising of how the moving average value Dn after maximum value Dn _MAX appeared load power value contents K
If the fall does not occur, the falling count is not added. Then, the moving average value Dn becomes the maximum value Dn.
_The falling count is sequentially added from the point in time when the load power value K decreases from _MAX . Therefore, when the signal falls have different time of appearance of the maximum value Dn _MAX of the moving average values differ in the mountain shape from its maximum value Dn _MAX only load power values contents K in the chart is substantially the same. And
As shown in FIG. 5, if the set value is set to 50, the first kneading end signal is output after 10 seconds (= 0.2 × 50), and the kneaded material properties of the kneaded material are stabilized.

As described above, by using the present embodiment, even if the load power value fluctuates unstable near the maximum value, it does not affect the determination of the kneading end time. Accordingly, the physical properties of the kneaded material at the end of kneading can be made extremely stable. By reducing the dispersion of the degree of dispersion, the tensile strength and elongation of the physical properties of the dough were stabilized at a high level.

[0025]

As described above, it is not necessary to determine the kneading end time in an unstable fluctuation state near the maximum value of the physical quantity detected every predetermined time. Therefore, the use of the rubber kneader control device and the control method of the present invention has an effect that the determination of the completion of kneading is accurate and the kneaded material properties of the kneaded material taken out of the rubber kneader are extremely stabilized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a control device for a rubber kneader according to a specific embodiment of the present invention.

FIG. 2 is a configuration diagram schematically showing a rubber kneader to which the apparatus of the embodiment is applied.

FIG. 3 is a flowchart showing a processing procedure of a CPU used in the apparatus of the embodiment.

FIG. 4 is a flowchart showing a processing procedure of a CPU used in the apparatus of the embodiment, which is subsequent to FIG. 3;

FIG. 5 is a chart showing a relationship between a kneading time and a load power value in the first kneading by the apparatus of the present embodiment.

FIG. 6 is a chart showing the relationship between the kneading time and the load power value in the first kneading by the apparatus of the present embodiment similar to FIG. 5;

FIG. 7 is a chart showing a relationship between a kneading time and a load power value in a kneading machine.

FIG. 8 is a chart showing a relationship between a kneading time and a load power value in a first kneading by a conventional apparatus.

FIG. 9 is a chart showing the relationship between the kneading time and the load power value in the first kneading by the conventional apparatus similar to FIG.

FIG. 10 is a block diagram illustrating the concept of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Rubber kneading machine 12 ... Drive motor 20 ... (For rubber kneading machine) Control device 23 ... CPU 24 ... ROM 25 ... RAM

Claims (2)

(57) [Claims] 1. A closed kneader having a pair of rotating members arranged adjacent to each other and rotating in opposite directions so as to be wound inward, and a pressing member driven so as to approach between the rotating members. A rubber kneader for kneading a kneaded product comprising a raw material rubber and an additive such as carbon black by rotating the rotating member and for the pressing member to press and knead the kneaded material between the rotating members. A controller for detecting a physical quantity related to a load of a drive source that rotationally drives the rotating member of the kneader during kneading at predetermined time intervals; and a maximum of the physical quantity detected by the physical quantity detecting means. A maximum value detecting means for obtaining a value; a determination value setting means for setting a value obtained by reducing a predetermined amount from the maximum value of the physical quantity as a determination value; And a kneading time determining means for determining a kneading end time based on a transition from a point in time at which the current value of the physical quantity exceeds the determination value set by the determination value setting means. Control device for rubber kneader. 2. A closed kneader having a pair of rotating members arranged adjacent to each other and rotating in opposite directions so as to wind inward, and a pressing member driven close to the rotating members. A rubber kneader for kneading a kneaded product comprising a raw material rubber and an additive such as carbon black by rotating the rotating member and for the pressing member to press and knead the kneaded material between the rotating members. In the control method, a physical quantity related to a load of a driving source that rotationally drives the rotating member of the kneader during kneading is detected at predetermined time intervals, a maximum value of the detected physical quantity is determined, and the maximum value of the physical quantity is determined. A value that is reduced by a predetermined amount from the value is set as a determination value, and a kneading end time is determined based on a transition from a point in time when the detected current value of the physical quantity exceeds the set determination value. Rubber kneading machine control method characterized by.